Freeze new generator and locales (#2886)

* Freeze new generator and locales

As we discussed here https://github.com/orgs/faker-ruby/discussions/2877
we want to improve faker's performance and organization. There hasn't been
to many bug reports and most of the open issues are related to performance
and confusion around using faker.

As we have limited time to invest in faker, reviewing new generators and
locales take lots of our time. With this decision, we hope to make the
necessary changes for faker to go to the next level.

* Reinforce what contributors we will accept during the freeze

CONTRIBUTING.md

@@ -81,14 +81,9 @@ There are a few ways to run RuboCop:
 
 ## Adding new generators/locales
 
-New generators will only be added to the gem after:
+The faker-ruby team has decided to stop accepting any new features, including generators and locales. Please see [What contributions we are looking for](#what-contributions-we-are-looking-for) for other ways you can help.
 
-- there's been a poll in the [community](https://github.com/orgs/faker-ruby/discussions/categories/new-feature-locale-generator). Use this to get feedback on how others would use it, what edge cases to cover, etc.
-- the community is interested in the feature.
-
-This allow us to measure the interest and see some traction before we decide to accept the proposal for a new generator.
-
-**Note**: we will not accept new generators/locales that do not follow the requirements above.
+This allows us to focus on improving the performance and organization of the library. We appreciate your understanding and we are looking forward to get your help with making faker faster and easier to use.
 
 ### General Guidelines
 

README.md

@@ -479,6 +479,8 @@ gem 'faker', :git => 'https://github.com/faker-ruby/faker.git', :branch => 'main
 
 ## Contributing
 
+**Note**: We are not accepting proposals for new generators and locales. The [Contributing](CONTRIBUTING.md) guide has a few notes about this decision.
+
 Take a look at the [Contributing](CONTRIBUTING.md) document for
 instructions on setting up the repo on your machine, opening bug reports, understanding the codebase,
 and creating a good pull request.